The present disclosure relates to a safety architecture, a battery and a motor vehicle having a corresponding battery that are able to be used particularly in order to combine battery packs of a relatively low safety integrity level to form a battery system having a relatively high safety integrity level.
For the supply of power to electric drives in electric and hybrid vehicles, high-voltage lithium ion batteries are frequently used. The chemistry in these batteries means that they have a hazard potential. By way of example, if operating limits are exceeded then a battery fire or leakage of dangerous chemical substances may occur.
Examples of safety-relevant operating limits are:                upper threshold for the charge (voltage) of a battery cell,        lower threshold for the charge (voltage) of a battery cell,        upper threshold for the temperature of a battery cell,        upper threshold for the charging current of a battery (temperature dependent).        
The charging and discharging of a battery are regulated by a battery management system (BMS) such that safety is assured under given requirements. For this, the sensor means, the logic and the actuator means need to be designed in line with the safety requirements or the safety integrity level (ASIL [Automotive Safety Integrity Level] from ISO 26262). Exceeding of the operating limits is usually monitored by monitoring functions, e.g. in the central logic.
Hybrid vehicles frequently require only relatively small batteries. The lower energy content means that these sometimes comply only with a low ASIL B.
By contrast, batteries for electric vehicles have to comply with a relatively high ASIL C or D on account of their higher hazard potential. This often has great repercussions on the software processes and the hardware structure. This is disadvantageous particularly because it means that different battery systems have conventionally had to be used on the basis of the safety requirements.